Kingdom Hearts: Between Light and Darkness
by Amarielah
Summary: When Heartless attack the Death Star, Princess Leia Organa and Darth Vader find themselves in Traverse Town, and form a temporary alliance in an effort to restore their world. While searching for answers, they get drawn into the fight for Kingdom Hearts. Star Wars/Kingdom Hearts/Disney/Final Fantasy crossover.
1. Chapter 1

Summary: When Heartless attack the Death Star, Princess Leia Organa and Darth Vader find themselves in Traverse Town, and form a temporary alliance in an effort to restore their world. While searching for answers, they get drawn into the fight for Kingdom Hearts. Star Wars/Kingdom Hearts/Disney/Final Fantasy crossover.

Disclaimer: I don't own Star Wars, Kingdom Hearts, any Disney properties, or any of the Final Fantasy games.

Timeline and canon notes: Takes place before and during KH1, with changes due to the presence of the Star Wars characters. The Final Fantasy characters come from their original games, because I think they're more interesting that way, with the exception of the kids from Destiny Islands (though a FFX version of Tidus is probably gonna show up at some point). Some Disney worlds that didn't show up in the games might make an appearance as well.

* * *

Leia remembers how the Heartless consumed the Death Star. Looking back, she suspects that they were drawn there by the smothering darkness that engulfed the so-called battle station. Perhaps, even, by the void left behind by so many lives being snuffed out with Alderaan.

She remembers sleek black bodies and yellow, glowing eyes, looking straight into her heart. Seeing the despair that she kept back behind a wall of determination. She had felt their hunger.

She had turned them away, somehow, before she'd been swallowed by what seemed like endless darkness.

And then she'd woken up in Traverse Town.

* * *

She isn't happy to find that Vader is there too, his dark form like a shadow from her nightmares. But he's about as congenial as he ever gets.

"You and I have a common goal, your highness," he says, his hulking form comically incongruous against the backdrop of the quaint little bistro, a wooden chair groaning in protest under his weight.

Leia scoffs. "Is this the part where you suggest we work together to restore our world, Lord Vader?"

"You're a resourceful young woman," he says, by way of confirmation.

"And _you're_ a monster," she replies coldly. She tries to push back the memory of him holding her in place as she had watched Alderaan burn.

"Indeed," he says easily. "But I fail to see how that's relevant to the situation at hand."

Leia feels her stomach churn in revulsion, even as she says, "I suppose I have little choice."

She's sure she's not imagining the smugness in his voice. "I'm glad you see the wisdom in this, your highness. These are...unusual times."

In spite of herself, Leia feels a smirk tugging at her lips. "I see that your talent for understatement is as impressive as your talent for theatrics."

A hiss of breath, which may or may not be a sound of amusement. "I'm glad that I can be of service," he says.

* * *

"You will return my lightsaber or suffer the consequences."

"Consequences, huh?" Yuffie doesn't look even remotely intimidated. "Like that thing where you choke people with you magic?" She grins like a fox. "You just try it, Darth Scuba. I don't think you'd like to try a level-three Fire spell on for size."

Leia sighs, wondering if she should try to intervene, before a new voice pipes in.

"Just give the man his damn laser sword back, ya brat. You'll only hurt yourself with it, anyway." Cid takes a drag of his cigarra. "And give me back my Fire materia while you're at it."

"Nuh-uh," Yuffie protests. "I got 'em both fair and square. It's not my fault that you two weren't paying attention."`

"Your ability to approach me undetected is most impressive," says Vader. "But my patience is wearing thin, youngling."

Cid takes his cigarra out of his mouth and tosses it to the pavement, stamping on it. "If you don't give 'em back now, I'll get Aerith to get 'em from you later."

Leia almost cringes on the girl's behalf. She's never met anyone as aggressively _nice _as Aerith, and yet with such a force of personality. She's considered asking her to join the Alliance more than once, though she knows she'd be turned down for sure.

Yuffie cringes on her own behalf, then sighs. "Okay, fine. Just...don't tell her about this." She tosses the lightsaber to Vader, who catches it telekinetically, then throws a small red orb to Cid.

"Showoff," mutters Cid, putting the orb into a slot on his wristband.

"According to the princess, that's the least of my flaws," replies Vader, hooking the lightsaber onto a clip on his belt.

"_The __p__rincess_ is standing right here," says Leia. She wonders then what a level-three Fire spell looks like, and what sort of damage it could deal to Vader's suit.

"Now don't you two start," says Cid. "I've got a new ship design I thought you might be interested in takin' a look at, Vader. Might actually be flyable."

"Certainly," says Vader.

"Also, don't threaten Yuffie again. She's a thief and a brat, but she doesn't deserve to die for it. And it'd be a shame to get rid of one of the few people in this shithole with half an understandin' of machines."

Leia senses the danger in the air as Vader says, "It is unwise to underestimate my power, Highwind."

Cid snorts. "Sure, you're powerful. But so 're Aerith and Squall. And me, if I get serious."

"I wouldn't worry," Leia says, glaring pointedly at the Sith Lord. "Lord Vader wouldn't sink so low as to murder a child. And certainly not over a matter that's so easily resolved without violence."

"That true, Vader?" asks Cid.

It's strange, but lately Leia has been...sensing things. Heartless approaching, and other people's emotions. When she'd first met him, Merlin had said that she had the potential to become powerful with magic, and she's starting to suspect that he wasn't entirely off-base. However much the thought unnerves her.

Right now, she's sure that she can sense Vader's discomfort.

"...Her highness is correct," says Vader.

"Well then, that's settled." Cid starts walking to the First District. "Let's get started."

* * *

"It must be frustrating for you," says Leia later, when the two of them are alone in the Red Room of the hotel, which has become their make-shift war room.

"There are many things I find frustrating at present, your highness."

Leia rolls her eyes, knowing that he's being deliberately obtuse. "I mean, being surrounded by people who are too powerful to push around. People who refuse to accept your authority."

"Frustrating is not the word I would use," he says, and she takes notice of the lack of a not-so-veiled threat directed at her. For the first few weeks, he'd constantly alluded to the fact that he could kill her with a thought. Perhaps he's finally realized that the threats mean nothing when it's obvious that he needs Leia for some future purpose, though she's not even sure he knows what it is yet. Otherwise he would've killed her already.

"Then what word _would_ you use?" she asks.

"Motivating."

Ah. So he wants to get to the matter at hand. "Subtle," she says.

"Subtlety is not a trait I've ever possessed."

"How completely unsurprising." She crosses her arms over her chest. "I suppose your meeting with Cid was fruitful, then."

"Yes," he says. "These "gummi ships" rely on bizarre technology, but we've managed to come up with a functional design. With the right materials, I may even be able to build something like a hyperdrive."

Leia still marvels at the fact that Cid and Vader actually seem to tolerate each other – and perhaps even enjoy each other's company – having found a common purpose in cobbling together a vessel from technology that neither of them were familiar with. If nothing else, Vader had yet to choke the man even once, in spite of Cid's complete lack of anything resembling deference.

"When do we leave, then?" she asks.

"It should take no more than two weeks to complete," he replies. "Once we've managed to salvage all the necessary parts, that is. And how quickly that goes depends on how cooperative the Moogles are."

Leia sighs. The Moogles are the true experts on all things gummi technology, but aren't the sort to part with their knowledge for free. In lieu of money, Vader had at first attempted to secure their cooperation with force.

It had been a spectacular failure, resulting in Squall summoning a powerful ice-controlling being called Shiva, and the Moogles raising their already steep regular rate by 50%. Afterward, she remembers Vader muttering something about them being worse than Jawas. His pride had been severely bruised ever since, which had been the only good thing to come out of the whole debacle.

"We already owe them a lot of money," says Leia.

"Money which we cannot get to them until we have a working ship," he says. A pause, and then, "There is something else I wish to discuss with you, your highness."

She gestures for him to go ahead.

He says nothing for a few moments, his mechanical breathing filling up the silence. Finally, he says, "I believe that the Force is with you."

For some reason, she isn't surprised. She's not entirely sure what the Force even is, but the words have a ring of truth to them. "I see," she says.

"I can train you in the ways of the Force," he continues. "As my apprentice, you would become more powerful than you can possibly imagine."

Leia rolls her eyes. "And then when we restore our world, we'll defeat the Emperor together and rule the Galaxy?"

"That was going to be part of my offer, yes." Though she senses he would have waited to say that part until she was already indoctrinated in his religion. "Our goals may not be as different as you think, princess, even if we disagree on the finer details."

The "finer details" being whether or not the galaxy should remain a totalitarian dictatorship, she suspects. "Well, I'm not interested," she says. "I've already received an offer to be trained by Merlin, and I think he's a far better option for me."

Vader's outrage is immediate. "That delusional old man will do nothing but hold you back."

"I disagree," she says, smiling. "Actually, I think I'm going to go tell him about my decision right now. He's sure to be thrilled."

She stands up and begins to leave, half-expecting him to stop her. But even though his rage is palpable, all he does is say, "Be mindful of the Heartless."

She stops at the door. "They're attracted to _you_, Lord Vader, not me. I'm sure that I'll be just fine."

His anger clings to her as she finally makes her way out of the hotel. She takes it as a victory.


	2. Chapter 2

Disclaimer: I don't own Star Wars, Kingdom Hearts, or anything by Disney and Square Enix.

Note: This chapter was hella fun to write. I really love putting Vader out of his depth.

* * *

Vader has trouble admitting it even to himself, but he finds the Aerith woman unnerving. He can barely sense her in the Force, as though she's millions of lightyears away. And yet, when she looks at him, it's as if she's seeing straight through his armor and into his very soul. It's shameful, but he does his best to avoid her when he can.

Unfortunately, she has a habit of running into him. Especially when he's in a particularly unpleasant mood.

Which he often is, after an extended conversation with the Princess. Who would likely already be dead due to her insolence under normal circumstances; but these are far from normal circumstances. He senses very strongly in the Force that she is somehow integral to restoring his world.

He's also certain that the Force is strong in her. And without his Master around to interfere, he could finally have a true Sith apprentice. And yet, there are several other complications to deal with. Ones that he could never have foreseen.

Like the woman standing before him now, smiling.

"Hello, Mr. Vader," she says.

He nods once in acknowledgment.

"You seem to be on your way to do something important," she continues, walking closer. "And you also seem very grumpy."

"How observant of you," he says, bristling at the word "grumpy". Had his dignity not already been impugned upon enough?

"Yup. Totally grumpy."

The little patience he has is wearing thin, so he says, "What is it that you want?"

Her smile widens. "I just wanted to say hello."

He can't sense enough from her to know if she's lying; he tries to reach out even further with the Force. But her mind is beyond his grasp, giving him nothing but psychic static. It does nothing to improve his mood.

"It's because I'm dead," she says brightly.

Vader startles out of his intense concentration, frowning under his mask. "What do you mean?"

"The reason why your powers don't react to me like normal people – it's because I'm dead." Her smile is very sweet. "I get the feeling that you've been wondering about it for a while."

Memories stir in the depths of Vader's mind, not entirely welcome for the remnants of Anakin Skywalker that resurface with them. Of Mortis, and the apparition who may have been Qui-Gon Jinn. "How is it possible for you to be here if you're dead?" he asks.

"I'm not entirely sure myself," she admits easily. "I think it might have to do with the fact that I managed to retain my identity in the Lifestream, and that I helped the others reach this place when the Heartless attacked." Her smile becomes apologetic. "I'm sorry. This probably doesn't mean much to you."

Actually, it all sounds very familiar. He thinks that the "Lifestream" is an apt enough name for the Living Force. "How were you able to maintain your identity in this Lifestream?"

She lets out a little giggle and clasps her hands behind her back. "I don't really remember that part either. Everything was much clearer when I was actually in it, you know?"

He can feel his irritation rising, and decides that now would be a good time to leave her presence. Vader is no coward. While he can indeed sense the immense power that the girl possesses, even distant as she is to him in the Force, it is not her potential retribution that he is wary of.

Rather, it's the fact that using the Dark Side draws the Heartless to him like rancors to raw meat. Of course, the Heartless are unusually attracted to him even when he doesn't use the Dark Side, but using it makes him especially vulnerable to their attempts to consume him. Even through the rush of power and control, he can feel them gnawing at the edges of his soul, eating away at what little of him is still human. It's motivated him to rein in his anger in a way he hasn't in years. Or at least to avoid situations that make him angry enough to tap into the Dark Side instinctively.

"Then you are of no use to me," he says, whirling around to walk in the opposite direction. He'll have to go to Merlin's through the Third District, it seems.

The Third District, which is crawling with Heartless.

She doesn't follow him.

* * *

He ignites his lightsaber the moment he enters the Third District, bile rising to the back of his throat as the cloying presence of Heartless envelops him. It's not unlike how he'd felt years ago as a Jedi when first confronted with places steeped in the Dark Side. And yet, even then, the Dark Side had held a certain allure – a promise of power.

The Heartless hold no such appeal.

Before they even come on the offensive, he can already feel them looking for cracks in his mental defenses, demanding entryinto the very depths of his soul. Their hunger for him is voracious.

He strikes down one of the little ones as it emerges from shadows on the pavement, and begins his slow progression towards the door of Merlin's keep. The Force at least can interact with Heartless that exist in corporeal form, and he uses it to repulse the flying beasts that approach him, lashing out with his lightsaber at those that manage to breach his defenses.

It's a struggle not to call on the power of the Dark Side as his anger at the creatures – and at his own weakness – begins to rise, beckoning him with its promise of swift and sure victory.

It's only the thoughts of becoming one of them – a death in all but name, or worse, with all individuality consumed by mindless aggression and hunger – that stops him from giving in.

He cannot deny the relief he feels when he finally reaches the red door leading to his destination, and feels Leia's presence beyond it. He had hoped to arrive after she was no longer there, but he supposes it makes little difference in the end.

He Force-jumps across the shifting rocks floating in the moat, and soon reaches the ramshackle house which the old wizard has taken up as his residence. He doesn't bother to announce his entry as he pushes aside the piece of fabric that serves as a make-shift door.

He finds that Leia and Merlin are sitting down together, drinking tea. Or at least, they were; Leia sets down her cup in order to properly glare at him.

"I don't recall inviting you to join us," she says.

"I did not come here to join your tea party," he replies. "I wish to speak to the old man. Alone."

Merlin's frown reminds Vader all too much of certain Jedi Masters, which only makes his irritation grow. "Well, this old man has no desire at all to speak with you alone. Now leave before I turn you into a...a rabbit!"

"I will end you before you can even try," Vader says.

Merlin stands up in a huff, knocking over his teacup in the process so that it shatters on the floor. "Oh, yes, yes – you're very frightening. I still expect you to leave me and my pupil in peace!" He notices the broken cup and stamps his foot. "Hang it all! That was one of my last ones!"

Leia stands as well, crossing her arms over her chest. "What exactly do you hope to accomplish here, Vader? I've already made my decision, and acting like a thug is not going to make me change my mind."

Vader allows some of his anger to flow into the Force – and the fact that it's a Jedi trick rankles him. But there's no denying that it's been very helpful in managing more delicate situations since arriving in this Force-forsaken place. "I will not harm him, your highness. I only wish to speak with him."

"Harm me?" exclaims the wizard. "Hah!"

"Whatever you have to say, you can say it with me here," says Leia.

"Very well." Vader raises his finger and points at Merlin. "It is not her highness' destiny to be your apprentice."

Leia rolls her eyes. "I don't believe in destiny, Lord Vader."

"Well I do," says Merlin. "But I see things very differently, indeed. Why, I've felt for weeks now that the Princess was going to accept my tutelage, and I was right! This "Force" nonsense may be all well and good in the world you come from, but it's next to useless against the Heartless. Just look at the way they swarm about you, like, like – the sorts of things that swarm about!"

"It's unwise to underestimate the Force, old man." Vader makes a fist to emphasize the point.

"And it's just as unwise to overestimate it!" Merlin snaps back. "I just bet you're the sort who thinks your powers can solve all of your problems."

"Enough of this," says Leia. "The decision is mine and mine alone." She glares hard at Vader. "If learning the ways of the Force will make me like you, then I have no interest in it. Accept my choice, Lord Vader, or our partnership is at an end."

Vader seethes, wishing very much that he could kill something or someone at that moment. But again, he lets his emotions flow out into the Force; he cannot afford to lose control. At length, he says, "As you wish, you highness. But I'm concerned that you're making a grave mistake."

Leia smiles tightly. "Well, we'll find out if that's the case soon enough, won't we?"

"Now then, that's all settled," says Merlin, throwing up his hands, and Vader feels his cloak being tugged towards the door. "I insist that you leave us be. Out, out, out!"

Vader wards off the invisible hands with a push of the Force, but stalks out of the house without further protest. He tells himself that Merlin may have won the battle, but that he's hardly won the war.

He has a ship to build, in any case.


End file.
